Terminal for electric-lamp glowers.



PATENTED NOV. 3, 1903.

H; POTTER. TERMINAL ron ELECTRIC LAMP GLOWERS.

APPLIOATIOF FILED MAY 1, 1903.

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Patented November S, 1903.

UNITED STATES PATENT OFFICE.

HENRY NOEL POTTER, OF NEW ROCHELLE, NEW YORK,-ASSIGNOR TO GEORGE WESTINGHOUSE, OF PITTSBURG, PENNSYLVANIA.

TERMINAL FOR ELECTRIC-LAMP GLOWERS.

SPECIFICATION forming part of Letters Patent No. 743,030, dated November 3, 1903.

Application filed May 1,1903- Serial No. 155,233. (No model.)

Be it known that I, HENRY NoEL POTTER, a citizen of the United States, and a resident; of New Rochelle, in the county of Westchester and State of New York, have invented a new and useful Improvement in Terminals for Electric-Lamp Glowers, of which the following is a specification.

My invention relates to electric-lamp glowers which are non-conductors at ordinary temperatures, but which become conductors when heated, and particularly to the terminals by means of which current is supplied thereto.

The object of myinvention is to provide a terminal the metal portion of which shall cover a large amount of surface and every point of which shall be substantially equidistant from a given point in the glower-axis.

On account of the extremely high temperatures at which glowers of the character above indicated are operated it has been found necessary to employ leading-in wires which are not only good conductors of electricity, but the material of which has a high melting-point and is substantially non-oxidizable in the atmosphere. Platinum wire is usually employed for this purpose, and various methods of making connection between such wires and the ends of the glowers have been devised. It has been the usual practice, however, to either wrap the wires around the ends of the glower and cover the convolutions with a coating of paste or to socket the ends of the terminal wires in the ends of the glower. Each of these general types of terminal has certain advantages over the other, but both lack the advantage which pertains to my present invention and is above referred to--that is, a uniform electrical drop from each point of the terminal to a given point in the axis of the glower.

One form of my invention is illustrated in the accompanyingdrawings, in Which-- Figure 1 is a View, partially in side elevation and partially in longitudinal section, of a partially-completed glower, and Fig. 2 is an end elevation of one of the terminals.

As indicated in Fig. 1, the left-hand terminal 2 is'attached to the glower-body 1, while the right-hand terminal is shown as detached from such body. The latter, while shown as solid, may, of course, be of tubular form, if

desired.

The terminal body 2 is shown as of frustoconical form, having a recess 3 in its smaller end and as having an outer end 4 in the form of a segment of a sphere. This outer end is 5 of platinum wire, the inner end of which terminates in a leading-in wire 6, the spiral beingeither pressed into the body 2 of the terminal or fastened thereto by means of a suitable cement coating.

The terminal may be of different shape from that specifically illustrated, and its metal portion may also differ structurally from what is shown, though the cup form is desirable as is also an open -work formation or such other surface irregularity as shall insure a secure gripping engagement between the metal and the body of normally non-conducting material.

The end of the glower-body 1 may be inserted in the recess 3 in the end of the terminal 2 and be cemented therein by a paste of material like or similar to that of the glower-body or a paste formed of such material and certain salts which will calcine when heatedsuch, for example, as one or more oxychlorids or nitrates of suitable metals.

Instead of forming the terminal bodies 2 separately from the glower-body 1 and comenting them in position the entire glower structure may of course be molded in a single piece, or the glower may be molded in two parts and fused together after being roasted, or the bodies 2 may be cemented or fused directly to the ends of the glower-body without the recesses 5. The terminalbodies may also be molded in position on the ends of the glower-body 1. In fact, any known and practicable method of construction may be employed, the essential feature of the invention residing in the distribution of the metal portion of the terminal, so that every part of it shall be I substantially equidistant from a given point in the axis of the body of the glower, whereby the current flowing into the shown as provided with a cup-shaped spiral face instead of being confined to a single I do point or other comparatively small surface,

and all parts of the terminal shall perform substantially the same service.

I claim as my invention- 1. An electric-lamp glower having a distributed or expanded metal terminal every portion of which is substantially equidistant from a given point in the axis of the glowerbody.

2. An electric-lamp glower havinga terminal the metal portion of which is distributed over a comparatively large surface and every point of which is substantially equidistant from a given point in the axis of the glower.

3. An electric-lamp glower having a metal 7 terminal in the form of a spiral so arranged that every point in its length is substantially pendently-formed terminal caps consisting of bodies of glower material-having sphericallycurved outer ends and open-work metal caps cemented to said ends.

7. An electric-lamp glower having enlarged terminals the outer ends of which are spherically curved and provided with metal caps.

8. An electric-lamp glower having enlarged terminals the outer ends of which are spherically curved and provided with openwork metal caps cemented thereto.

9. An electric-lamp glower having enlarged terminals of glower material, within the outer surfaces of which are embedded laterally-expanded open-work metal terminals.

10. An electric-lamp glowerhaving at one or both ends terminal caps consisting of bodies of glower material, in which are embedded laterally-expanded open-Work metal terminals.

11. An electric-lamp glower having laterally-expanded metal terminals the electrical drop between substantially all portions of which and the active portion of the glower shall be equal.

In testimony whereof I have hereunto subscribed my name this 24th day of April, 1903.

HENRY NOEL POTTER.

Witnesses:

VWM. H. CAPEL, THos. H. BROWN, Jr. 

